1,916 research outputs found

    Doxorubicin-induced F-actin reorganization in cofilin-1 (nonmuscle) down-regulated CHO AA8 cells.

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    The actin cytoskeleton plays an important role in many cellular processes, including cell mortality, mitosis, cytokinesis, intracellular transport, endocytosis and secretion but also is involved in gene transcription. The dynamics of the actin cytoskeleton is controlled by different classes of actin-binding proteins (ABPs) which regulate the polymerization of actin filaments. In this report we used siRNA against cofilin-1 (nonmuscle) to demonstrate the effect of cofilin on the nuclear and cytoplasmic actin pools in CHO AA8 cells after exposition to various concentrations of doxorubicin. The immunofluorescence studies showed doxorubicin dose dependent tendency to formation the multinucleated giant cells, but also the increase of fluorescence intensity of cofilin in nuclei of untransfected cells. Induction of cell death with doxorubicin treatment in untransfected cells revealed both mitotic catastrophe (in both lower and higher doxorubicin doses) and apoptosis (mostly in higher doxorubicin doses), whereas among cofilin-1 down-regulated cells we observed only mitotic catastrophe. The results suggest that cofilin has apoptosis-inducing ability and that mitotic catastrophe is independent from F-actin content in cell nucleus. In this point of view we conclude that different mechanisms of chromatin reorganization are involved in these two processes. Moreover, we suppose that apoptosis and mitotic catastrophe are independent from each other

    Electron microscope study of the advanced tendinopathy process of the long head of the biceps brachii tendon treated arthroscopically

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    Background: The ultrastructural alterations related to tendinopathy have not been well described. Most studies on this subject have been conducted many years ago and focused on material from the Achilles tendon. It was demonstrated that various comorbidities can affect ultrastructural alterations in the advanced tendinopathy; however, there is very little data on ultrastructural morphology in tendinopathies related to mechanical overload as in case of the long head of the biceps brachii tendon (LHBT). The aim was to determine intermediate ultrastructural alterations in middle to severe grade the LHBT tendinopathy and to establish if they are different than those reported in the literature for other anatomical locations. Materials and methods: In this study we examined the ultrastructure of a series of the LHBT fragments arthroscopically removed due to tendinopathy and inve­stigated the morphology of tenocytes and collagen fibres in cases of the LHBT tendinopathy. Results: In pathological samples tenocytes were randomly scattered, their shape was round and the shape of nuclei was also disrupted. The presence of apoptotic­-like features in tenocytes’ nuclei was noted. All samples showed replacement of collagen fibrils by non-collagen extracellular matrix and diffuse collagen disorganisation. Conclusions: It was demonstrated at ultrastructural level that the LHBT tendino­pathy is not simply a wear and tear phenomenon, since chronic degeneration of the extracellular matrix and tenocytes were present, similarly as in tendinopathies, in other anatomical locations. (Folia Morphol 2018; 77, 2: 371–377

    Sonography in the instability of the long head of the biceps tendon confronted with histopathologic and arthroscopic findings

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    Background: Disorders of the long head of the biceps (LHB) tendon are a common source of shoulder pain and disability. This tendon can be well visualised using ultrasonography; however, little is known if such examination allows clinicians to predict pathological changes of the tendon structure. In the study described below, we compare preoperative sonographic findings with the data from shoulder arthroscopy and microscopic examination of the excised tendon fragments in 19 consecutive patients with LHB tendinopathy and clinical suspicion of its instability.Materials and methods: Preoperative ultrasonographic (US) inspection assessed several features of the tendon, whereas its stability was verified arthroscopically. In all cases, tenodesis or tenotomy procedures were performed and excised tendon fragments were harvested for microscopic examination based on the semiquantitative Bonar score.Results: The most common US findings were hypoechoic areas, tendon thickening, an increased power Doppler signal and mechanical instability. Just as shoulder arthroscopy confirmed all mechanical instability cases detected in US, microscopic assessment revealed advanced degeneration in all samples.Conclusions: Our study indicates that US is a useful tool in identifying cases of advanced instability and LHB tendinopathy, whereas biceps tendon instability is a biomechanically complex, gradually progressing phenomenon, frequently associated with additional shoulder lesions

    Tendon — function-related structure, simple healing process and mysterious ageing

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    Tendons are connective tissue structures of paramount importance to human ability of locomotion. The understanding of their physiology and pathology is gaining importance as advances in regenerative medicine are being made today. So far, very few studies were conducted to extend the knowledge about pathology, healing response and management of tendon lesions. In this paper we summarise actual knowledge on structure, process of healing and ageing of the tendons. The structure of tendon is optimised for the best performance of the tissue. Despite the simplicity of the healing response, numerous studies showed that the problems with full recovery are common and much more significant than we thought; that is why we discussed the issue of immobilisation and mechanical stimulation during healing process. The phenomenon of tendons’ ageing is poorly understood. Although it seems to be a natural and painless process, it is completely different from degeneration in tendinopathy. Recent studies of biological treatment reported faster and optimal healing of the tendons when augmented by growth factors and stem cells. Despite advances in biology of tendons, management of their injuries is still a challenge for physicians; therefore, further studies are required to improve treatment outcomes

    Process of neovascularisation compared with pain intensity in tendinopathy of the long head of the biceps brachii tendon associated with concomitant shoulder disorders, after arthroscopic treatment. Microscopic evaluation supported by immunohistochemical

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    Background: Tendinopathy of the long head of the biceps brachii tendon (LHBT) is one of the most common, painful conditions of the anterior part of the shoulder and often coexists with rotator cuff tears. Multifactorial aetiopathology of tendi­nopathy is poorly understood; however, several studies indicated that it is seen predominantly in areas with decreased vascularity of the tissue; the pathology is also characterised by expansive and abundant neovascular in-growth. The aim of the study was to investigate the relationship between the neovascularisation of proximal part of the LHBT and pain along the bicipital groove. Materials and methods: Tissue material was obtained from 28 patients who underwent a shoulder arthroscopy and experienced pain along the bicipital groove measured using Visual-Analog Scale (VAS) score. CD31 and CD34 molecules were visualised by immunohistochemical method to assess biceps tendon neovascula­risation and quantify it based on a Bonar scoring system. Results: Although all patients reported pain prior to arthroscopy (mean VAS score was 7.5), microscopic examination did not reveal neovascularisation in all cases. Immunohistochemical staining for CD31 and CD34 allowed for very precise visualisation and quantification of neovascularisation; however there was also no correlation between vessels in-growth scores and pain. Conclusions: The obtained data suggest that neovascularisation process in tendino­pathy is not directly related to pain; however, further studies are needed to explain its significance in the LHBT tendinopathy. (Folia Morphol 2018; 77, 2: 378–385

    Nanocrystalline materials studied by powder diffraction line profile analysis

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    X-ray powder diffraction is a powerful tool for characterising the microstructure of crystalline materials in terms of size and strain. It is widely applied for nanocrystalline materials, especially since other methods, in particular electron microscopy is, on the one hand tedious and time consuming, on the other hand, due to the often metastable states of nanomaterials it might change their microstructures. It is attempted to overview the applications of microstructure characterization by powder diffraction on nanocrystalline metals, alloys, ceramics and carbon base materials. Whenever opportunity is given, the data provided by the X-ray method are compared and discussed together with results of electron microscopy. Since the topic is vast we do not try to cover the entire field

    Evaluation of the Safety of Neauvia Stimulate Injectable Product in Patients with Autoimmune Thyroid Diseases Based on Histopathological Examinations and Retrospective Analysis of Medical Records

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    The aim of this study was to test the effect of hyaluronic acid cross-linked with polyethylene glycol containing micronized portions of calcium hydroxyapatite (Neauvia Stimulate) on both local tissue and systemic consequences, which are crucial from the perspective of long-term safety, in patients suffering from Hashimoto's disease. This most common autoimmune disease is a frequently mentioned contraindication to the use of fillers based on hyaluronic acid as well as biostimulants based on calcium hydroxyapatite. Broad-spectrum aspects of histopathology were analyzed to identify key features of inflammatory infiltration before the procedure and 5, 21, and 150 days after the procedure. A statistically significant effect on the reduction of the intensity of the inflammatory infiltration in the tissue in relation to the state before the procedure was demonstrated, combined with a reduction in the occurrence of both antigen-recognizing (CD4) and cytotoxic (CD8) T lymphocytes. With complete statistical certainty, it was demonstrated that the treatment with Neauvia Stimulate had no effect on the levels of these antibodies. All this corresponds with the risk analysis that showed no alarming symptoms during the time of observation. The choice of hyaluronic acid fillers cross-linked with polyethylene glycol should be considered justified and safe in the case of patients suffering from Hashimoto's disease

    Proton-proton elastic scattering at the LHC energy of {\surd} = 7 TeV

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    Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at {\surd}s = 7 TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (sbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t|, the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of d t = 0.1GeV p|t|. In this letter, first results of the differential cross section are presented covering a |t|-range from 0.36 to 2.5GeV2. The differential cross-section in the range 0.36 < |t| < 0.47 GeV2 is described by an exponential with a slope parameter B = (23.6{\pm}0.5stat {\pm}0.4syst)GeV-2, followed by a significant diffractive minimum at |t| = (0.53{\pm}0.01stat{\pm}0.01syst)GeV2. For |t|-values larger than ~ 1.5GeV2, the cross-section exhibits a power law behaviour with an exponent of -7.8_\pm} 0.3stat{\pm}0.1syst. When compared to predictions based on the different available models, the data show a strong discriminative power despite the small t-range covered.Comment: 12pages, 5 figures, CERN preprin

    Diamond Detectors for the TOTEM Timing Upgrade

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    This paper describes the design and the performance of the timing detector developed by the TOTEM Collaboration for the Roman Pots (RPs) to measure the Time-Of-Flight (TOF) of the protons produced in central diffractive interactions at the LHC. The measurement of the TOF of the protons allows the determination of the longitudinal position of the proton interaction vertex and its association with one of the vertices reconstructed by the CMS detectors. The TOF detector is based on single crystal Chemical Vapor Deposition (scCVD) diamond plates and is designed to measure the protons TOF with about 50 ps time precision. This upgrade to the TOTEM apparatus will be used in the LHC run 2 and will tag the central diffractive events up to an interaction pileup of about 1. A dedicated fast and low noise electronics for the signal amplification has been developed. The digitization of the diamond signal is performed by sampling the waveform. After introducing the physics studies that will most profit from the addition of these new detectors, we discuss in detail the optimization and the performance of the first TOF detector installed in the LHC in November 2015.Comment: 26 pages, 18 figures, 2 tables, submitted for publication to JINS
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